Generally, ammunition (ammo) magazines for weapons, such as guns, do not have a low ammunition indicator. The user will simply open a magazine lid and check the ammo level, or there will be a viewing window in the lid that lets the user see how much is remaining.
Ammunition magazines are used in harsh and moving environments. Ammunition can easily shift inside the magazine as a turret moves and rotates in several combinations of movements. In addition, there are remote turret applications where a user does not have access to check the ammo level. Reliable magazines are required in such environments.